Category: Scientific American

The editorial column of the February 2008 issue of Scientific American includes a call for the presidential candidates to have a debate over issues of science and technology.

Consider this partial list of issues that the next president of the U.S. will need to address: reducing greenhouse gas emissions; ensuring freshwater supplies; encouraging reliance on renewable energy sources; preparing for pandemics; developing stem cell technologies; improving science education; stimulating technological innovation. How many of the current candidates for the presidency have stated clear positions on those subjects?

Do any of the presidential candidates have a clue when it comes to science? Should they? Or can they get by by relying on advisers? (My answer is that I’d prefer a scientifically-literate president, but I’m not sure who that would be).

A new book is out: The World Without Us. This isn’t some left-wing or Islamo-fascist book about how much better the world would be without the United States. This is speculative science, and I don’t use the word “speculative” in a negative sense. The book asks the question: “What would happen to the Earth if suddenly, all people were removed?”

There is a serious side to this speculation, and that is the question of the extent of the impact of human activities on the environment. How long will toxic organic chemicals persist in groundwater? How long will it take for plastics to decompose? What will happen to the structures we build if we don’t maintain them?

This doesn’t seem to be a book of the hyper-environmentalist humans-are-a-disease genre. Some on the vocal fringes of the environmental movement view humans as a cancer that is destroying the pristine Earth, and that the planet would be better off without us. The book doesn’t seem to be advocating anything of the sort.

The July 2007 issue of Scientific American has a full-length article on this book, which includes an interview with the book’s author, Alan Weisman. Here are the first two paragraphs from the article:

It’s a common fantasy to imagine that you’re the last person left alive on earth. But what if all human beings were suddenly whisked off the planet? That premise is the starting point for The World without Us, a new book by science writer Alan Weisman, an associate professor of journalism at the University of Arizona. In this extended thought experiment, Weisman does not specify exactly what finishes off Homo sapiens; instead he simply assumes the abrupt disappearance of our species and projects the sequence of events that would most likely occur in the years, decades and centuries afterward.

According to Weisman, large parts of our physical infrastructure would begin to crumble almost immediately. Without street cleaners and road crews, our grand boulevards and superhighways would start to crack and buckle in a matter of months. Over the following decades many houses and office buildings would collapse, but some ordinary items would resist decay for an extraordinarily long time. Stainless-steel pots, for example, could last for millennia, especially if they were buried in the weed-covered mounds that used to be our kitchens. And certain common plastics might remain intact for hundreds of thousands of years; they would not break down until microbes evolved the ability to consume them.

Here’s a few items from Weisman’s timeline for Manhattan without Man:

2 days — New York City subways flood.

7 days — Nuclear power plants melt down or burn.

5 years — Much of New York burns.

100 years — The steel in skyscrapers corrodes to the point that buildings begin to topple.

300 years — New York’s suspension bridges collapse.

15,000 years — Last stone buildings fall.

10,000,000 years — Only human relics that have survived are bronze sculptures.

Do not store up for yourselves treasures on earth, where moth and rust destroy, and where thieves break in and steal. But store up for yourselves treasures in heaven, where moth and rust do not destroy, and where thieves do not break in and steal. For where your treasure is, there your heart will be also. (Matthew 6:19-21 NIV)

All the great works of man will eventually turn to dust. Some of the stuff we want to last a long time doesn’t last; and some of the stuff we want to go away quickly is going to be with us for a long, long time.

Back in October, I wrote a post about the idea of introducing large mammals (elephants, camels, lions, and so on) into the high plains of the United States (see Pleistocene mega-fauna — coming to a drive-thru safari park near you). The idea is to somewhat restore the pre-human ecosystem by bringing in mammals that went extinct at about the same time that humans arrived in North America. Elephants would fit into the niche that mammoths occupied, camels were native to North America, and lions would fill the role of large carnivorous cat.

Scientific American magazine offers some of its articles online for free. Free material from the October issue includes Impact From the Deep, which gives evidence that some mass-extinctions in Earth history were not caused by asteroid impacts but by massive upwellings of hydrogen sulfide (H2S) gas from the oceans. Here’s the scenario:

High levels of volcanic activity leading to high levels of atmospheric CO2 and methane.

Increase in global atmospheric temperatures due to a stronger greenhouse effect.

Lower oceanic oxygen content allows H2S-rich water from depth to rise to the surface.

Poisonous H2S causes mass-extinctions in the oceans.

H2S diffuses into the atmosphere, killing many land plants and animals.

The level of atmospheric CO2 that accompanied this bubbling of oceanic H2S was around 1000 ppm. The current CO2 concentration is 385 ppm, with an increase of 2-3 ppm per year. At this rate, CO2 could be at 900 ppm by the end of the century. The warning: Higher levels of greenhouse gases in the atmosphere could lead not only to global climate change, but also to global H2S asphixiation.

Here is my initial response:

The article was written by Peter Ward, one of the authors of the respected book Rare Earth. That gives it credibility.

The data seems sound. We can get a good understanding of past global CO2 levels, H2S levels, and rates of extinction through carbon isotope studies and paleontology.

From the following graph, There were also long periods of elevated CO2 levels which did not lead to mass-extinctions. This may be the greatest weakness of the hypothesis.

Graphic from Scientific American

Because of this, the investigators may have a good hypothesis, but it still needs work.

Of course, many will dismiss this as the just the latest unlikely disaster scenario from wild tree-hugging environmentalist wackos. But if it is to be dismissed, it should be on scientific merits, not because of a knee-jerk reaction.

Do the concepts of expertise and excellence lead to a narrow focus on one thing, to the exclusion of all else? Does the kind of focus that it takes to become a top computer programmer necessarily mean that person will be the stereotypical “computer nerd?” I think not. Take the late Harvard paleontologist Stephen Jay Gould. He had his passions—not only paleontology and evolution but baseball as well, and could write intelligently about a wide range of subjects. His ability to draw from so many different areas is one thing that made him a very readable author (The Panda’s Thumb, Wonderful Life, many others).

I would say that for someone to be a leader or expert in one’s field, it is necessary to be broad as well as deep. I don’t just read about science and science education; I read books and articles about theology, geography, history, politics, culture, philosophy. The key is to find the right balance—and I do not claim to have found that balance yet—and to look for ties between the area of one’s expertise and the wider world. This breadth enables the expert to more effectively relate the significance of his or her work to others who have different areas of interest.

According to the August 2006 Scientific American article “The Expert Mind,” motivation and effortful study are more important than natural ability for becoming and expert in one’s field. It takes ten years of intense work to truly become an expert in an area, but most people stop working at it far short of expertise.